The present invention relates to an elevator installation with a linear drive system and a linear drive system for an elevator installation.
Different elevator configurations with linear motor drive systems are known. However, in elevator configurations of that kind the most diverse problems arise, which previously could be solved only in part. This is due to the fact, inter alia, that the problems are in part diametrically opposed and the isolated solution of one of the problems is frequently accompanied by problems in other areas.
This conflict is explained in the following by way of an example. Linear motor drive systems, particularly those operating with permanent magnets, have very high attraction forces between a primary- or stationary-part and a secondary- or movable-part. If use is now made of such a permanent magnet linear motor not only as a direct drive system, but also as support means of the elevator car then a precise and secure guidance of the elevator car has to be guaranteed. With respect thereto FIGS. 1A, 1B, 2A and 2B show different basic configurations of prior art elevator installations with permanent magnet linear drive systems.
A configuration is shown in FIGS. 1A and 1B in which an elevator car 13 is moved by means of a permanent magnet linear drive system 10, 11 along an elevator shaft in a “y” direction. Such a permanent magnet linear drive system typically comprises a stationary part 10, which is fastened in the shaft, and a movable part 11, which is fastened to the elevator car 13. It can be seen from the plan view in FIG. 1B that no guidance in the “y-z” plane is effected in such a configuration, so that additional guide shoes have to be provided at the elevator car 13 to guide the elevator car 13 along guide rails 12 arranged on the right and the left near the elevator car 13. A comparable elevator installation is shown in the European patent application EP 0 785 162 A1.
Another basic configuration is shown in FIGS. 2A and 2B. As can be seen in the plan view in FIG. 2B, the permanent magnet linear drive system comprises a stationary part 10 and two movable parts 12. Guidance in the “y-z” plane is thereby achieved. However, in order to avoid tipping in the “x-y” plane guide rails are similarly necessary or the elevator car 13 is carried by further support means such as a cable 12′ mounted centrally at the elevator car.
The previously known approaches are therefore technically complicated, require much material and space in the elevator shaft and are thus cost-intensive.
In addition, the known solutions are not suitable or are only conditionally suitable for elevator installations in rucksack configuration, which for constructional or aesthetic reasons require only one wall of the elevator shaft for drive, support means and guidance.